Flexible grip with intermediate member

ABSTRACT

A flexible tubular implement grip with a first section formed of elastomeric material having a first set of properties and a second section having a second different set of properties. An annular interface member is disposed between and abutted and bonded to the first and second section on opposite sides of the interface member. The interface member is fitted on a core bar and inserted therewith in a mold. The materials of different properties are then disposed concurrently in the mold, either for compression molding or by injection and cured in a single molding operation. The interface member may have grooves on the inner or outer periphery to provide positive interlocking engagement of the elastomeric material with the interface member.

BACKGROUND

The present disclosure relates to flexible grips for implements of the type to be manually swung with speed and force, for example, hammers, axes, hatchets, and sporting equipment such as tennis racquets and golf clubs. In particular, the disclosure relates to flexible elastomeric grips for golf clubs.

Presently golf club grips are fabricated with different areas of the grip having different properties relating to the function and performance of the club in play. For example, the upper and lower portions of the gripping area have been provided with elastomeric material having different hardness and/or surface characteristics. In such arrangements, the upper area of the grip may be formed of softer or lower durometer elastomeric material for greater comfort and gripability; whereas, the lower portion of the grip may be harder rubber for maintaining stability of the grip. As shown in FIG. 1, a typical flexible golf club grip may have an end cap 2 fused thereto at the upper end thereof.

Implements grips such as golf club grips have been heretofore made by disposing the elastomer having different properties in specific areas of a mold, which upon closing, and vulcanizing cures the different elastomeric material which fuses together. Alternatively, the flexible grip may be made in a two-step process wherein a material having a first set of properties is injected into a mold and cured to form a portion of the grip, the molded first portion is removed from the mold and inserted in a second mold, where the second material with different properties from the first portion is injected and the material with properties different from the first portion is cured and fused to the first portion. This technique has been employed to provide a molded underlist for the first portion of the grip and over-molding a second material of different properties over the underlist in the second mold.

Heretofore, it has also been the practice to provide a cap over the upper end of the molded tubular grip; and, typically a pre-molded cap is disposed in the mold and is fused to the remaining portions of the grip during the curing. This technique of providing an end cap has been employed where the body of the tubular grip is formed both by compression molding and by injection molding for fusing the cap to the body of the grip.

Where different materials are employed for a first and second portion such as the upper and lower portion of the flexible grip, the problem that has arisen where the two different materials meet in the mold, and where the different materials meet and have fused during molding, migration of one of the materials into the other occurs. Where the different materials employed are of different color, or, for example, where one of the materials comprises a logo, the migration during molding of one material into the other where the different materials meet produces an undesirable appearance and is generally unacceptable for visual aesthetics and marketing purposes. Furthermore, where different materials are employed in the flexible grip and compression molding is used, the time required to dispose the different materials in the mold has been deemed prohibitive for volume production of golf club grips. Where injection molding has been employed, the time required for removing a first portion cured from a first mold and inserting the first molded portion into a second mold for injection molding the second portion of a different material, has been found to be excessive and quite costly for high volume production. Accordingly, it has been desired to find a way or means of cost-effectively molding a flexible implement grip, particularly a golf club grip, with materials having different properties, which may include different colors, in a manner which is cost-effective for high volume production rates and which eliminates the migration of the different materials, one into the other, during molding.

SUMMARY

The present disclosure describes a flexible grip for the handle of an implement of the type to be swung with speed and force, and particularly for use with golf clubs. The flexible grip of the present disclosures provides for forming a portion of the grip such as the upper portion of a golf club grip, with a flexible material having different properties than the material employed for the lower portion, in a manner which is cost-effective for volume production and which prevents migration of the different materials at the junction of the two materials, one into the other, thereby eliminating any undesirable visual effects associated therewith.

The flexible grip of the present disclosure provides an annular interface member which, may be pre-cured completely or partially, is inserted in a mold; and concurrently, the materials having different properties are inserted in the mold on opposite sides of the annular interface member. The different materials with different properties are then uniformly cured in the mold and are fused to the opposite sides of the annular interface member which prevents migration of the different materials, one into the other. The annular interface member may be employed with either compression molding, or injection molding in which case eliminates the need for a separate second mold. In addition, a separate annular interface member may be disposed in the mold at the upper end of the grip and a cap may be disposed adjacent the distal side of the second annular interface member and fused thereto during molding.

The technique of fabrication of a flexible grip of the present disclosure readily facilitates the one-step fabrication of a grip with elastomeric materials having different properties. Where injection molding is employed, the injection may be simultaneous, i.e., dual or closely proximate serial injection of the materials of different properties for a single stage molding of the complete grip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a known flexible elastomeric golf club grip having a tubular body portion and an end cap fused to the upper or distal end of the body;

FIG. 2 is a view similar to that shown in FIG. 1 of one version of a grip of the present disclosure with upper and lower portion formed of elastomeric materials having different properties;

FIG. 3 is a perspective view of one version of an annular interface member employed in the grip of FIG. 2;

FIG. 4 is another version of an annular interface employed in the grip of FIG. 2;

FIG. 5 is a portion of a section view taken along section indicating lines 5-5 of FIG. 2;

FIG. 6 is a view similar to that shown in FIG. 2 showing the grip removed from the mold after simultaneous injection of elastomeric materials having different properties;

FIG. 7 is a perspective view of a portion of another version of the grip employing another annular interface member between the cap and the upper portion of the tubular grip;

FIG. 8 is a perspective view of another version of the flexible grip having the annular interface member disposed at a bias angle to the axis of the grip;

FIG. 9 is a perspective view of another version of the grip having an annular interface member forming two opposite bias angles with the longitudinal axis of the grip;

FIG. 10 is a perspective view of another version of the flexible grip of the present disclosure having an annular insert between the upper and lower portions with contra-curvature in the insert;

FIG. 11 is a perspective view of a portion of another version of the annular interface member which extending radially for a portion of the wall thickness of the tubular grip and having a plurality of circumferential grooves formed therein in the outer periphery;

FIG. 12 is a portion of a section view taken through the longitudinal axis of a grip having elastomeric materials with different properties on opposite sides of the annular interface member of FIG. 11;

FIG. 13 is a view similar to FIG. 11 illustrating another version of the annular interface member having circumferential and axial grooves formed in the outer periphery thereof;

FIG. 14 is a view similar to that shown in FIG. 12 showing in a longitudinal cross-section another version of a grip having the annular interface member extending completely through the wall of the tubular grip with grooves on the inner periphery;

FIG. 15 is a view similar to that shown in FIG. 11 illustrating another version of the annular interface member having a central circumferential groove in the outer periphery with transverse or axial voids formed therein for penetration of different materials on opposite sides thereof;

FIG. 16 is a view similar to that shown in FIG. 14 showing the annular interface member of FIG. 15 in axial cross-section as disposed in a completed grip; and

FIG. 17 is a portion of an axial cross-section of a mold with a core bar, annular interface member, and materials of different properties on opposite sides thereof for single stage curing in the mold.

DETAILED DESCRIPTION

Referring to FIG. 2, one embodiment of the flexible grip of the present disclosure is indicated generally at 10 and has a first, or lower, tubular section 12 with one set of properties abutting an annular interface member 14 on one axial face thereof with a second, or upper, tubular section 16 of elastomeric material having different properties from the lower section 12 abutting the opposite axial face of member 14. The different properties may include durometer hardness, density, composition, and color. An end cap 18 is fused to the distal or upper end of the second section 16. In the present practice, it has been found satisfactory to have the annular interface member 14 formed of partially or completely pre-cured elastomeric material. In the present practice, it has been found satisfactory for the cap 18 to have a durometer hardness greater than the material of either the lower section 12 or upper section 16.

The annular interface member 14 is illustrated in perspective view in FIG. 3. In the present practice employed for member 14, the elastomeric materials may be thermoplastic or thermosetting.

Referring to FIG. 17, In the present practice, the annular interface member 14 is placed over a core bar 17, and the core bar 17 with the annular interlace member 14 thereon is placed in a mold 15, whereupon elastomeric material 19, 21 respectively, having different properties is disposed in the mold on opposite sides of the annular interlace member 14. Mold 15 is configured such that when the mold is closed, the mold radially compresses the annular interface member 14, wherein the inner periphery thereof is pressed against the outer surface of the core bar 17; and, the outer periphery of the annular interlace member 14 is compressed against the inner surface of the mold 15. This arrangement prevents the elastomeric material on opposite sides thereof from flowing around the annular interface member 14. It will be understood that the annular interface member 14 is chosen of material which is capable of bonding to the adjacent elastomeric materials 19, 21 on opposite sides thereof.

Thus, the inclusion of the annular interface member 14 permits the deposition of the elastomeric materials 19, 21 having different properties on opposite sides of the interface member in a single mold; and, subsequent curing to be performed in a single molding operation to produce a completed grip upon removal from the mold 15 and core 17. The technique of the present disclosure is readily adapted to simultaneous or rapid serial injection molding of the materials of different properties for the upper and lower sections 14, 12, respectively; and, particularly advantageous where the materials for the sections 14, 12 are formed of material having different colors or which include a logo thereon.

Referring to FIG. 4, another version of the annular interface is indicated at 20 and has the inner periphery thereof formed with a plurality of axially extending grooves, indicated typically at 22, formed circumferentially spaced about the inner periphery thereof. The grooves 22 permit the elastomeric material 19, 21 disposed on opposite sides thereof to flow through the grooves and fuse together providing positive interlocking engagement to enhance securing the annular interface member into the completed grip.

Referring to FIG. 5, a portion of a grip is shown in axial cross-section, the completed grip having the annular interface member 14 of FIG. 3 disposed between the upper and lower tubular sections 12, 14.

Referring to FIG. 6, a perspective view of the completed grip is shown as it would appear employing either of the interface 14 of FIG. 3 or the interface 20 of FIG. 4 and an end cap.

Referring to FIG. 7, another version of the grip of the present disclosure is shown in perspective, indicated at 30, and has an upper tubular section 32 thereof with a second annular insert 34 disposed adjacent the distal or upper end of section 32 and intermediate an end cap 36 received onto the face of the annular interface member 34 opposite the upper section of the grip 32. It will be understood that the annular interface member 34 may have a configuration of either FIG. 3 or FIG. 4.

Referring to FIG. 8, another version of the grip of the present disclosure is shown in perspective, indicated generally at 40, and has a lower tubular section 42 with an annular interface member 44 adjacent the upper end of the lower section 42 and has an upper tubular section 46 disposed adjacent the axial face of the annular interface member 44 opposite the lower section 42 and has an end cap 48 disposed over the upper end of section 46. The annular interface member 44, as shown in FIG. 8, is disposed at a bias angle to the longitudinal axis of the grip and thus gives the distinctive appearance which may be advantageous for appearance and marketing purposes.

Referring to FIG. 9, another version of the flexible grip of the present disclosure is shown in perspective, indicated generally at 50, and has a lower tubular section 52 with an annular interface member 54 disposed adjacent the upper end of the section 52 and an upper tubular section 56 having its lower end fused to the upper face of the inner face member 54 with the upper section 56 having an end cap 58 fused over the upper end thereof. In the version 50, the annular interface member 54 is formed to have adjacent sections 55, 57 thereof formed at opposite bias angles to the longitudinal axis of the grip 50. This arrangement thus gives a different and unique appearance for the outer surface of the grip upon completion of the molding operation.

Referring to FIG. 10, another version of the grip of the present disclosure is illustrated in perspective, indicated generally at 60, and has an annular interface member 62 disposed between a lower tubular section 64 and an upper tubular section 66; and the version 60 has an end cap 68 fused over the upper end thereof. The annular interface member 62 has the axially opposite faces thereof alternating in a manner producing contra-curvature with respect to the longitudinal axis of the grip, with the faces denoted respectively by the reference numerals 63, 65 in FIG. 10. The appearance of the interface member 62, upon removal of the grip from the mold, gives a different and unique appearance to the outer surface of the grip, particularly where the annular interface member is formed of a material having a different color than that of either of the lower section 64 or upper section 66, which may have advantages for aesthetic appeal and marketing.

Referring to FIGS. 11 and 12, another version of an annular interface member is indicated generally at 70 and has a plurality of circumferentially extending grooves 72 formed therein. As shown in FIG. 12, the member 70 extends radially only partially through the wall of the grip sections 74, 76. Upon insertion in the mold and the molding of sections 74, 76 of material having different properties respectively, on opposite sides thereof, the materials 74, 76 flow into the grooves 72 and fuse together over the outer periphery of the member 70 such that the member 70 is not visible from the outer surface of the grip. The grooves 72, by virtue of the material of the sections 74, 76 being disposed therein during molding provide a positive interlocking engagement therewith.

Referring to FIGS. 13 and 14, another version of the annular interface member is indicated generally at 80 and has a peripherally extending annular groove 82 formed therein and at least one and generally a plurality of transverse or axially extending grooves 84 formed therein. The grooves 82, 84 form positive interlocking and retention of the annular member and the grip. The flow of the materials from the respective upper and lower sections of the grip 86, 88 is shown in dashed line in FIG. 14. The annular interface member 80, as illustrated in FIG. 13, has its radial thickness coinciding with the radial thickness of the wall of the upper section 88 and lower section 86 such that the material flowing into the grooves 82, 84 is visible on the exterior surface 85 of the finished grip and gives a somewhat cruciform appearance to the materials in the groove which may produce a unique appearance, particularly where the sections 86, 84 comprise materials of a different color.

Referring to FIG. 14, another version of the grip denoted generally at 80′ is shown with a circumferential groove 86 on the inner periphery of an interface member 87, with axial grooves 88, 89 indicated in dashed line formed on the inner periphery on opposite sides of groove 86. The interface member 87 is thus inverted with respect to the interface member 80 of FIG. 13. However, as shown in FIG. 14, the interface member 87 extends radially the full thickness of the adjacent lower and upper sections 12′, 16′ of the grip 80′. In molding, the grip 80′, the material from the adjacent lower and upper sections 12′, 16′ thus flows along a core bar such as core bar 17 of FIG. 17 (not shown in FIG. 14) through grooves 88, 89 into the groove 86. Alternatively, an interface member (not shown) may employ grooves on the inner and outer periphery.

Referring to FIGS. 15 and 16, another version of the annular interface of the present disclosure is indicated generally at 90 and has a circumferential or peripheral groove 92 formed therein and has apertures 94, 96 formed respectively in the opposite side walls of the groove 92 which apertures 94, 96 extend therethrough in an axial direction. As shown in FIG. 16 in dashed outline, the apertures 94, 96 permit the material for the adjacent lower section 98 and upper section 100 of the grip to flow through the apertures 94, 96 and into the region of the groove 92 to provide positive interlocking engagement; and, to provide an annular band 102 visible on the exterior surface of the grip which may be a composite of the materials in the sections 98, 100. The band 102 thus may have a unique appearance, particularly where the sections 98, 100 are formed of materials of different colors.

The flexible grip of the present disclosure utilizes an annular interface member disposed between a first or lower tubular section and a second or upper tubular section of the grip which may be formed of materials having different properties such as durometer hardness and/or color. In one version, the annular interface has grooves on the inner periphery to permit material from the upper and lower section to flow therethrough during molding; and, in other versions, the annular interface may have grooves in the outer periphery to provide flow of materials from the adjacent upper and lower sections therein to provide positive interlocking or distinct appearance on the exterior of the grip. Other versions of the annular interface provide for the member to be disposed at a bias angle to the axis of the grip or have a contra-curvature appearance. The annular interface member of the present disclosure is disposed over a core bar and inserted into a mold whereupon the materials having different properties are disposed on opposite sides of the annular interlace and cured in one operation to form a completed grip. Where the annular interface extends completely through the wall thickness of the grip, it is compressed between the core bar and the inner surface of the mold to prevent flow of the material therearound. The arrangement of the annular interface thus permits concurrent or simultaneous disposition of the materials of different properties in the mold, either for single stage compression molding or concurrently or simultaneously by injection molding.

The present disclosure thus describes the grip which may be formed with different materials for the upper and lower sections for a first and second portion and cured in a single molding operation, thereby providing a cost-effective method of manufacturing.

The exemplary embodiment has been described and illustrated with reference to the drawings. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. 

1. A flexible grip for a golf club shaft comprising: (a) a first tubular section formed of elastomeric material having a first set of properties; (b) a second tubular section formed of elastomeric material having a second set of properties different from the first set; (c) an annular interface member formed of elastomeric material disposed intermediate the first and second tubular sections wherein the material of the first section is bonded to the annular interface member on one side thereof and the material of the second tubular section is bonded to the annular interface on a side opposite the one side; and, (d) wherein the annular interface member includes certain surfaces thereon engaging corresponding surfaces on the first and second tubular sections in positive interlocking relationship.
 2. The flexible grip of claim 1, wherein the certain surfaces include one of (i) axially extending grooves, and (ii) circumferentially extending grooves, wherein the grooves are formed on one of (i) an inner periphery, and (ii) an outer periphery of the annular member.
 3. The flexible grip of claim 1, wherein the annular member extends one of (i) partially, and (ii) completely through a thickness in a radial direction of the first and second tubular section.
 4. The flexible grip of claim 1, further comprising an end cap disposed on the second tubular section with a second annular interface member disposed between the end cap and the second tubular section.
 5. The flexible grip of claim 1, wherein the annular interface member is formed of one of (i) cured thermoplastic, (ii) partially cured thermoplastic, and (iii) thermosetting elastomer.
 6. The flexible grip of claim 1, wherein the first and second set of properties have a different including one of (i) durometer hardness, (ii) color, (iii) composition, and (iv) density.
 7. A method of making a flexible tubular grip for the handle of an implement of the type to be moved with speed and force comprising: (a) disposing an annular interface member on a core bar; (b) inserting the core bar with the annular interface member thereon in a mold; (c) concurrently injecting elastomeric material having a first set of properties on one side of the interface member and elastomeric material having a second set of properties into the mold on the side of the annular interface member opposite the one side and forming the grip; (d) curing the grip in the mold; and, (e) removing the grip from the mold and removing the core bar from the grip.
 8. The method of claim 7, wherein concurrently injecting includes one of (i) simultaneously injecting into the mold, and (ii) serially injecting into the mold.
 9. The method of claim 7, wherein disposing an annular interface member includes forming certain positive interlocking surfaces on the annular interface member on one of (i) the inner, and (ii) the outer periphery thereof.
 10. The method of claim 7, wherein concurrently injecting includes injecting elastomeric material with one of the first and second set of properties having a Mooney viscosity less than
 38. 